This invention relates to data transfer of vehicular tire and wheel information, and more particularly to a vehicular dual tag tire and wheel radio frequency identification system which uses both a tire tag including tire information, and a wheel tag including wheel information, of a tire/wheel assembly to store and transfer identification and specific integrity information.
It is desirable to monitor the condition of tires as to wear, internal temperature and internal pressure. It is particularly advantageous to monitor large truck tires since these are expensive and must be regularly maintained to maximize vehicle efficiency. In the past, such monitoring activities generally used a passive integrated circuit embedded within the body of the tire and activated by a radio frequency transmission which energizes the circuit by inductive magnetic coupling. Passive devices which rely on inductive magnetic coupling or capacitive coupling generally have the disadvantage of requiring lengthy coil windings, thus requiring major modifications in the tire construction and assembly process. Another serious disadvantage with such passive devices is that an interrogator must be positioned in very close proximity to the tire, usually within a few inches of the tire, in order to allow communication between the tire and the device. Because of the proximity requirements, continuous monitoring is impractical since it would require that an interrogator be mounted at each wheel of the vehicle. Manual acquisition of data from the passive devices embedded in each of the tires of a parked vehicle is also cumbersome and time consuming because of the proximity requirements.
Another disadvantage with known tire monitoring and identification devices is that communication transmissions are achieved using conventional radio frequencies which generally require a relatively large antenna which must be mounted externally or secured to the tire in such a manner which requires relatively major modifications in the tire construction or assembly process.
Prior approaches to monitoring tire conditions and identification with various communication techniques have met with limited success. In one approach disclosed in U.S. Pat. No. 5,960,844, a method for monitoring tires was depicted. The method included an activatable memory device or tag permanently mounted within at least one tire of a vehicle on the inner surface. The device contained stored data pertaining to the tire, and in which the memory device was activated by means of a monitoring device mounted on the tire rim within the pressurizable cavity formed within the tire.
In a different approach shown in U.S. Pat. No. 5,573,610, a method for monitoring various conditions of pneumatic tires and to tires containing a monitoring device was depicted. The invention disclosed a method of monitoring tires which used an active, self-powered, programmable electronic device which was generally installed in or on the interior portion of a pneumatic tire or on a tire rim. The device could be used for monitoring, storing and telemetering information such as temperature, pressure, tire mileage and/or other operating conditions of a pneumatic tire along with tire identification information.
In yet another approach, U.S. Pat. No. 5,562,787, a method of monitoring tires was provided in which an activatable monitoring device or tag was mounted within at least one tire of a vehicle, on the interior surface thereof, or on the tire rim. The device was activated by means of an interrogator signal having a frequency in the microwave range. In response to the signal, the monitoring device measured and transmitted information relating to one or more conditions such as the internal pressure and temperature of the tire, the number of rotations of the tire, and tire identification information. The monitoring device was secured within the tire in such a manner and location as to minimize stress, strain, cyclic fatigue, impact and vibration.
In still yet another approach, U.S. Pat. No. 5,573,611, the invention depicted was a method of monitoring tires which used an active, self-powered programmable electronic device which was installed in or on the interior surface of a pneumatic tire or on a tire rim. The device was activated by externally transmitted radio frequency waves and in response, the device compared or transmitted information and provided a warning in the event a preselected limit was exceeded. An interrogator was used to communicate with and retrieve digitally coded information from the electronic monitoring device.
In U.S. Pat. No. 5,838,229, a system for indicating low tire pressure in vehicles was depicted. Each vehicle wheel had a transmitter with a unique code. A central receiver in the vehicle was taught, at manufacture, to recognize the codes for the respective transmitters for the vehicle, and also a common transmitter code, in the event one of the transmitters needed to be replaced. During vehicle operation and maintenance, when the tires were rotated, the system could be recalibrated to relearn the locations of the transmitters.
In another application, U.S. Pat. No. 5,731,754, the invention included a transponder and sensor apparatus with on-board power supply mounted in or on a vehicle tire. A pressure sensor, a temperature sensor and a tire rotation sensor were mounted in a housing along with the transponder, the power supply and an antenna. Upon receipt of an interrogation signal from a remote interrogator, the transponder activated the sensors to sense tire pressure and temperature and then backscatter-modulate the radio frequency signal from the interrogator with the tire condition parameter data from the sensors to return the backscatter modulated signal to the interrogator.
In yet another application, U.S. Pat. No. 5,977,870, a method for monitoring various engineering conditions of a pneumatic tire such as temperature, pressure, tire rotation and other operating conditions of the tire was depicted. A tire tag was mounted on the interior of the tire within the pressurizable cavity and contained the stored data and sensors for detecting certain conditions within the cavity. A separate transponding device was mounted on the tire rim. The tire tag contained a battery, an antenna and stored data pertaining to the tire. The transponding device used electronic circuitry for collecting data from the tire tag. The tire tag was actuated by transmitted radio frequency waves from the transponding device, which data was transmitted by the transponding device to the remote location by an antenna which extended from the transponding device through the rim to a location externally of the tire.
In spite of the teachings of the above-mentioned patents, there is still a significant need for a tire and wheel monitoring system for sensing, storing and transmitting condition data on command from an interrogator that would preserve the data should either the tire or wheel be discarded. This will mean that the tire and wheel data storage site and other pertinent information such as pressure and temperature sensing, will remain relatively protected on the wheel or tire. This will also eliminate the potential for the monitoring tag negatively affecting the integrity of the tire. For example, when the tire is replaced, this will also ensure that the temperature/pressure sensing technology will remain on the wheel with the vehicle. As tires wear out and are replaced, the old tire""s identification and information can be read from the new tire and written to the wheel tag for protected storage.
The present invention relates to a dual tag tire and wheel radio frequency identification (RFID) system in a tire/wheel assembly of a vehicle. The system is capable of sending tire and wheel condition parameter data to a remote interrogator in response to a radio frequency (RF) signal from the remote interrogator. The system comprises a tire tag located on a tire of a tire/wheel assembly with RF read/write capability, and a wheel tag located on a wheel of the tire/wheel assembly with RF read/write capability. Both tags also have the ability to store data pertinent to wheel and tire condition. This system provides a tire and wheel monitoring system that will not lose stored data should either the tire or the wheel of a tire/wheel assembly be discarded due to rotation, replacement or destruction. In addition, the placement of a tag on the wheel will eliminate the potential for the tire tag and/or tire pressure and temperature monitoring to negatively affect the integrity of the tire. This design will also ensure that pertinent tire condition data such as temperature/pressure sensing technology will remain on the wheel with the vehicle.
In a preferred embodiment of the invention, the system includes a temporary RFID tag located on an interior surface of a tire. A permanent RFID tag is located on a wheel. Once the tire is mounted on the wheel a remote interrogator could read the tire identification and information from the tire RFID tag and then write this information to the RFID tag on the wheel. This process would transfer the tire identification and information from the tire RFID tag to the wheel RFID tag. The RFID tag on the tire would only have to be robust enough to survive until the tire identification and information is transferred to the RFID tag on the wheel. In this embodiment the wheel RFID tag would act not only as a tire pressure monitoring system (TPMS) but would also serve as a remote database for the identification and information of both the tire and the wheel. As tires wear out and are replaced, the old tire""s identification and information could be erased and the new tire""s identification and information could be read from the new tire and written to the wheel RFID tag for protected storage.
In an alternative preferred embodiment the system of the present invention includes a temporary RFID tag for the wheel. Replacement or destruction of the wheel would ensure that identification and other information is preserved because of storage on the tire RFID tag.